... Also to finish my relatively long post from page 6...
I think that the main
purpose of every game
genre or better said of classification of games into specific genres is to give a brief
indication to players and readers of paper and online gaming magazines,
what can they
expect from the
game they have never seen or tried before.
I remember my local paper magazine's review section was divided into entire sub-sections according to supposed videogame genres, so that a reader could easily find out what was new in his favorite genre.
If I go by traditional "treshold system", than if I read that a game is supposedly an RPG, I can imgagine that a game will probably have some of the features like skills system, leveling system, strong emphasis on story, inventories and various equipment, loot, most likely some kind of combat sections, conversations with NPCs, at least little bit of exploration and non-linearity, main quests and sidequests, (I am sure I have omitted some good stuff:P), etc.
Now, if I could truly and fully trust that the reviewer or whoever is talking about the game has a similar perception of the "treshold system" as I do, and has decided to call a game an RPG, than I can almost safely approach the game, because it will most likely have a lot of the abovementioned features, which I like.
However, if somebody considers a game an RPG because
it is a game that tries to allow me to pretend that I am a main character of the game and make decisions for that character, what am I supposed to imagine when he says that he played a good RPG?
Is it an action game or a non-combat game or both? Is it linear or non-linear? How does it work? What mechanics does it use?
All I can presume is that a game has "some" kind of system or mechanism which would allow me to act in different ways in different situations - most likely in conversations with other characters. But not much more.

Now if I compare it with somebody who again follows the same "treshold" approach as I do, and he says, Mass Effect 2 is an (TP) action / RPG hybrid, I can presume that at least some of the features like skills system, leveling system, strong emphasis on story, inventories and various equipment, loot, most likely some kind of combat sections, conversations with NPCs, at least little bit of exploration and non-linearity, main quests and sidequests, etc. made it to the game in addition to probably strong presence of action elements.
It's not perfect, but I still have an idea how Mass Effect 2 supposedly works.
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So, like I said. I have nothing against the definition itself... IMO it's very pure and close to original meaning of words like "role" and "playing", but it is IMO soo broad and uncertain that it
starts to diminish the purpose of classification (of games in different genres)
itself.
Anyway, thank you for wishing us not to get hit by cars.

It's a very rare wish and thus is very appreciated.